1. Field of the Invention
The present invention relates to a sound processing device, a sound processing method, and a sound processing program.
2. Description of Related Art
In recent years, robots such as humanoids or home robots performing social interactions with persons have actively been studied. The study of musical interaction in which a robot is allowed to hear music and is allowed to sing a song or to move its body to the music is important to allow the robot to give a natural and rich expression. In this field of technology, for example, a technique of extracting a beat interval in real time from a music signal collected by the use of a microphone and causing a robot to dance to the beat interval has been proposed (for example, see Japanese Unexamined Patent Application, First Publication No. 2010-026513).
In order to allow a robot to hear speech or music, it is necessary to mount a sound collecting device such as a microphone on the robot. However, sound collected by the sound collecting device of the robot includes a variety of noise. The sound collected by the sound collecting device includes as noise, for example, a variety of sound generated by the robot itself as well as environmental sound generated around the robot. Examples of the sound generated by the robot itself include the footsteps of the robot, the operational sound of motors driven in its body, and spontaneous speech. In this way, when the S/N ratio of the collected audio signal is lowered, accuracy of speech recognition is lowered. Accordingly, a technique of improving a recognition rate of the speech recognition by controlling a robot so as to suppress the operational sound of the robot when speech is uttered by a user while the robot operates has been proposed (for example, see Japanese Patent No. 4468777).